On Friday, the agency said, federal marshals seized 500 doses of live Vaccinia virus vaccine for smallpox belonging to StemImmune Inc., a San Diego firm that develops stem cell-based immunotherapies for cancer. The raid came after the F.D.A. learned that the vaccine was being used to create an unapproved stem cell product, a combination of excess amounts of vaccine and stem cells derived from body fat, which was then administered to cancer patients with potentially compromised immune systems.
The F.D.A. said patients at the California Stem Cell Treatment Centers in Rancho Mirage and Beverly Hills, Calif., received the treatment made with the smallpox vaccine. It also said it had serious concerns about how StemImmune obtained the vaccine for use in an unapproved and potentially dangerous treatment.
StemImmune obtained at least some of the vaccine from the Centers for Disease Control and Prevention, according to Thomas Skinner, a C.D.C. spokesman. In its request, the company said it was conducting cancer research involving the vaccinia virus, and needed to vaccinate researchers — a seemingly legitimate reason. The company did not tell the C.D.C. that it was going to inject the vaccine into patients, he said.
A statement from StemImmune said the company had lawfully obtained the drug.
The F.D.A. also issued a warning letter to U.S. Stem Cell, a private clinic in Sunrise, Fla. The company was the subject of a March report in The New England Journal of Medicine, describing how one woman went blind and two others suffered severe, permanent eye damage after being given shots of stem cells, extracted from fat, into their eyes.
The warning letter accused the company of impairing the F.D.A.’s ability to conduct its inspection by refusing to allow inspectors in, and denying them access to employees. It also said that U.S. Stem Cell had failed to establish proper quality control and sanitary standards.
In a statement Monday afternoon, U.S. Stem Cell denied ever restricting access to F.D.A. inspectors, or having sterility problems. “The safety and health of our patients are our number one priority and the strict standards that we have in place follow the laws of the Food and Drug Administration,” it said.
Noting that the F.D.A. has asked patients with concerns to come forward, the company said it had asked patients who have had positive experiences with their stem cell treatments to notify the agency.
But in the warning letter, the F.D.A. noted that U.S. Stem Cell had claimed its work was not subject to agency regulation. The F.D.A. disagreed, saying that the cells extracted by the company met the definition of both a drug and a biological product, both of which come under the agency’s jurisdiction. In its statement, U.S. Stem Cell said it would abide by the new rules the agency is developing for the field.
Dr. Gottlieb said it was imperative to shut down fraudulent and unsafe players in the field in order to take advantage of the promise of stem cell therapies and to increase innovation in the regenerative medicine field, a program authorized by Congress in the 21st Century Cures Act.
Those enterprises “put the entire field at risk,” Dr. Gottlieb said. “Products that are reliably and carefully developed will be harder to advance if bad actors are able to make hollow claims and market unsafe science.”
The California Stem Cell Treatment Centers were founded in 2010 by Dr. Mark Berman, a plastic surgeon, and Dr. Elliot Lander, a urologist. Dr. Berman defended the company, and said that the F.D.A. had not accurately interpreted its cancer pilot study with StemImmune. Dr. Berman, who is also a director of StemImmune, also said that none of the patients had experienced serious adverse effects or died as a result of the treatment involving the vaccine, which he noted, was free.
Dr. Berman and Dr. Lander also train other physicians to perform liposuction, extract stem cells from the fat and inject the cells to treat many ailments, including heart disease, back and knee pain, asthma and neurological disorders.
After training, the physicians can become affiliates of the Cell Surgical Network, which has more than 60 members around the country. Patients are charged $8,900 per procedure, Dr. Berman said in a previous interview. He said affiliates purchase a centrifuge and incubator from the network for about $29,000, and pay the network $1,000 for the disposable liposuction equipment needed for each procedure.
A Florida woman, Doris Tyler, 77, lost her sight after being treated last September at an affiliate of the Cell Surgical Network, the Ageless Wellness Center in Peachtree City, Ga. Cells from her fat were injected into both eyes.
Before the treatment, Mrs. Tyler’s sight had deteriorated because of age-related macular degeneration. But she said she could still see well enough to get around, cook and read.
Within a month of the injections, Mrs. Tyler had a retinal detachment and lost the sight in her left eye. A few weeks later, the same thing happened to her right eye.
She consulted Dr. Thomas Albini, an eye surgeon at the Bascom-Palmer Eye Institute at the University of Miami, who had also examined the three women who went blind after similar treatment at the U.S. Stem Cell Clinic.
In an interview, Dr. Albini said Mrs. Tyler’s case resembled the others. The stem cells apparently formed a membrane that pulled the retina off the back of the eye, causing blindness. Attempts to reattach the retinas surgically could not restore Mrs. Tyler’s sight. She was permanently blinded.
Calls to the clinic in Peachtree City were not returned.
Dr. Berman said that because of her case, affiliates of the Cell Surgical Network were being advised to avoid giving injections directly into the eyes.
“We made a bad decision to have this done,” Mrs. Tyler’s husband said.
Dr. Gottlieb said the F.D.A. would soon publish documents detailing which new treatments and products are subject to agency regulation, and which are not, and giving details on a new, expedited path for companies with legitimate products, seeking premarket approval.
Some industry representatives applauded the move.
“The F.D.A.’s proposal is clear evidence of the fact that the regenerative medicine sector has matured and has moved from just a research sector to a development of market ready products,” said Michael Werner, a partner in the law firm of Holland & Knight and the executive director of the Alliance for Regenerative Medicine. “He’s clearly distinguishing unscrupulous actors who are playing upon hype and taking advantage of patients and product developers who are actually going to treat diseases.”
‘He is trying to balance patient safety and a regulatory pathway that is as least burdensome as possible,” Mr. Werner said.
Public health advocates praised the F.D.A. for moving against the companies, but said it should have happened sooner, given the widespread knowledge of public harm.
“We certainly welcome this type of action, although it comes belatedly,” said Dr. Michael Carome, director of Public Citizen’s Health Research Group. “The agency has known about these unscrupulous actors for years.”